C’è qualcuno con quale posso condividere tutto questo lavoro?
Is there someone with whom I can share all this work?

Note the optional use of the relative pronouns on whom in the English in the first example, whilst with whom is necessary in both Italian and English.

Devo incontrare qualcuno alle tre
I have to meet someone at three o’clock

Nessuno/a

This is invariably singular. In positive phrases it means no-one or nobody, or just none. However, in negative phrases it means anyone or anybody; it is simply rank bad English grammar to say I don’t know nobody! In negative phrases remember that non goes before the verb.

Ognuno nel gruppo ha la sua responsibilità specificaEach one in the team has their (or his/her) own specific responsibility.

Note that in Italian you should use the singular sua and not the plural loro, whilst in English it is common to see the singular (each one, everyone) and plural (their) used.

C’erano tante fotografie che dovevo dare ad ognuna un numero serie diverso
There were so many photographs that I had to give each one a different identification number.

Chiunque

This is only used in respect of people, never animals or things, and is invariable, ie it has no plural although it may refer to more than one person. When used in a relative sentence or clause, it takes the subjunctive mood of the verb to which it relates. You can find out more about the subjunctive mood under Verbs.

Chiunque sia, può andare viaWhoever it is, they (he/she) can go away

See the note above relating to ognuno.

Qualcosa

This refers to things, not people or animals. It too is invariable. Note that it is considered masculine, despite cosa (thing) being feminine.

C’è qualcosa che ho dimenticato
There is something that I have forgotten

Non è qualcosa che voglio ricordare
It is not something I want to remember

These are the plurals of alcuno and alcuna, and can be used as indefinite pronouns when referring to people. As is the general case in Italian, when you are referring in general terms to both men and women, you must use the masculine form, alcuni. You can also use this when referring to men only. Use alcune when you refer to just women. You will find that alcuno, alcuna, alcuni and alcune are also used as adjectives.

C’è qualcos’altro che posso fare di aiutarti?
Is there anything else I can do to help you?

Notice the elision, ie the final letter ‘a’ of qualcosa is dropped and is replaced with an apostrophe. This is something that often happens in Italian.

There are a few idiomatic expressions that use altro as a pronoun. Two examples are:

Senz’altro! Certainly!Altro che! No wonder!

Niente, nulla

Again these are invariable. Where they are used after a verb the negative non must appear before the verb.

Nulla è più bello che stare in amoreNothing is more beautiful than being in love

Non c’è niente che posso fare di aiutarlo
There is nothing I can do to help him

Tale/i

You will find this used most of the time as an adjective. However, it can be used as a pronoun to referring to an unidentified person. In this way, it equates to the English terms bloke or chap, and requires either un or quel.

This means both, and therefore is plural. It can be used by itself, but is more commonly followed by di + either the subject pronoun or the direct object pronoun. You will also see it after the subject pronoun, serving as a form of emphasis.

Entrambe erano state buone amiche fino a quando hanno litigato l’una con l’altraBoth women had been good friends until they fell out with each other